-- 设备成本归设备台账维护；运营页只读取，不另设一份手工分成参数。
-- NULL 表示尚未从设备档案迁入，不能用默认成本伪造回本结果。可重复执行。
SET @cost_column_exists = (SELECT COUNT(*) FROM information_schema.columns
 WHERE table_schema = DATABASE() AND table_name = 'sa_device' AND column_name = 'cost_price');
SET @cost_ddl = IF(@cost_column_exists = 0,
 'ALTER TABLE sa_device ADD COLUMN cost_price DECIMAL(10,2) UNSIGNED NULL COMMENT ''设备台账成本，对应旧 market_goods.cost_price''',
 'SELECT 1');
PREPARE cost_statement FROM @cost_ddl;
EXECUTE cost_statement;
DEALLOCATE PREPARE cost_statement;

-- 撤下误加的参数编辑权限；保留历史表与角色关系，避免破坏已有审计数据。
UPDATE sa_system_menu SET status=2, delete_time=COALESCE(delete_time,NOW()), update_time=NOW()
 WHERE slug='core:operation:device:update';